Roof type charging apparatus using resonant power transmission

ABSTRACT

Provided is a roof-type charging apparatus that charges multi-target device, while transmitting a resonance power. A roof-type charging apparatus using resonance power transmission includes a source resonance unit configured to transmit resonance power including a source resonator having a generally planar loop configuration and defining a space therein; a receiving unit configured to receive the resonance power transmitted from the source resonator; and a connecting unit configured to separate the source resonator and the receiving unit by a predetermined distance.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit under 35 U.S.C. §119(a) of KoreanPatent Application No. 10-2010-0087939, filed on Sep. 8, 2010, in theKorean Intellectual Property Office, the entire disclosure of which isincorporated herein by reference for all purposes.

TECHNICAL FIELD

The following description relates to apparatuses and method for charginga multi-target device, while transmitting a resonance power.

BACKGROUND

As demand for portable electrical devices has increased, use of wiredpower supplies has become inconvenient. Studies on wireless powertransmission have been conducted to overcome inconveniences of wiredpower supplies and the limited capacity of conventional batteries.Commonly used mobile devices may perform wireless charging based on aninduction scheme that uses a frequency, for example, ranging from dozensof kilohertz (kHz) to hundreds of kHz. The induction scheme may beefficient in wireless power transmission. However, to performconventional wireless power transmission, induction coils are close toeach other, and a location of a center of a wireless power transmissioncoil may be the same as a wireless power reception coil. Thus, theinduction scheme may have a limited charging scope, and may not be ableto perform charging that simultaneously charges a plurality of mobiledevices using a single wireless power transmission coil.

SUMMARY

According to an aspect, a roof-type charging apparatus using resonancepower transmission comprises: a source resonance unit configured totransmit resonance power including a source resonator having a generallyplanar loop configuration and defining a space therein; a receiving unitconfigured to receive the resonance power transmitted from the sourceresonator; and a connecting unit configured to separate the sourceresonator and the receiving unit by a predetermined distance.

According to an aspect, the source resonator and the receiving unit arepositioned generally parallel with respect to one another.

According to an aspect, the source resonator is one of: square-shaped,rectangular-shaped, circle-shaped, oval-shaped, elliptical-shaped,triangle-shaped, octagon-shaped and polygon-shaped.

According to an aspect, the source resonator defines an effectivecharging radius of the source resonator.

According to an aspect, a target resonator that receives the resonancepower transmission is positioned inside the effective charging radius ofthe source resonator.

According to an aspect, the apparatus further comprises: an input powerunit configured to generate a resonance power based on a resonancefrequency, and to provide the resonance power to the source resonator.

According to an aspect, the input power unit is located below the spacedefined by the source resonator.

According to an aspect, the apparatus further comprises: a matching unitconfigured to match a coupling impedance of the source resonator and atarget resonator that receives the resonance power transmission.

According to an aspect, the matching unit is positioned in the spacedefined by the source resonator.

According to an aspect, the source resonance unit includes a frameconfigured to connect the source resonator to the connecting unit.

According to an aspect, the apparatus further comprises: a powerconverter configured to convert alternating current (AC) power of avoltage source to a direct current (DC) power.

According to an aspect, the connecting unit comprises a hollow cylinder,and a cable passing through the inside of the hollow cylinder.

According to an aspect, the hollow cylinder is formed of an insulativematerial.

According to an aspect, the predetermined distance is adjustable therebyproviding impedance matching between the source resonator and a targetresonator that receives the resonance power transmission.

According to an aspect, the source resonance unit includes an extensioncontroller configured to adjust an effective charging radius of thesource resonator.

According to an aspect, the apparatus further comprises: a supportingunit configured to support the apparatus.

According to an aspect, a method of transmitting resonance powercomprises: transmitting resonance power using a source resonator havinga generally planar loop configuration defining a space therein; andreceiving with a receiving unit the resonance power transmitted from thesource resonator, wherein the source resonator and the receiving unitare separated by a predetermined distance.

According to an aspect, the source resonator is one of: square-shaped,rectangular-shaped, circle-shaped, triangle-shaped, octagon-shaped andpolygon-shaped.

According to an aspect, the source resonator defines an effectivecharging radius of the source resonator.

According to an aspect, a target resonator that receives the resonancepower transmission is positioned inside the effective charging radius ofthe source resonator.

According to an aspect, the method further comprises: adjusting thepredetermined distance to provide impedance matching between the sourceresonator and a target resonator that receives the resonance powertransmission.

According to an aspect, the method further comprises: adjusting aneffective charging radius of the source resonator.

According to an aspect, a roof-type charging apparatus using resonancepower transmission comprises: a source resonance unit configured totransmit resonance power including a source resonator having a generallyplanar loop configuration and defining a space therein; a receiving unitconfigured to receive the resonance power transmitted from the sourceresonator; a matching unit located in a predetermined area of a frame ofthe source resonator and configured to match, to a predetermined value,a coupling impedance between the source resonator and at least onetarget resonator that receives the resonance power transmission; aninput power unit configured to generate resonance power based on aresonance frequency, and to provide the resonance power to the sourceresonator; a connecting unit configured to separate the source resonatorand the receiving unit by a predetermined distance; and a supportingunit connected to the input power unit and configured to support theroof-type charging apparatus.

According to an aspect, a source resonance unit configured to transmitresonance power comprises: a source resonator having a generally planarloop configuration and defining a space therein.

Other features and aspects may be apparent from the following detaileddescription, the drawings, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating a wireless power transmission system.

FIGS. 2A through 2C relate to a pad-type charging apparatus usingresonance power transmission.

FIG. 3 is a diagram illustrating a roof-type charging apparatus usingresonance power transmission.

FIG. 4 is a diagram illustrating a location where a target device ischarged in a roof-type charging apparatus using resonance powertransmission.

FIG. 5 is a diagram illustrating resonance power transmission based on alocation of a target resonator in a resonance power receiver.

FIG. 6 is a diagram illustrating various examples of source resonators.

FIG. 7 is a diagram illustrating various examples of roof-type chargingapparatuses which use resonance power transmission.

FIG. 8 is a diagram illustrating a resonator having a two-dimensional(2D) structure.

FIG. 9 is a diagram illustrating a resonator having a three-dimensional(3D) structure.

FIG. 10 is a diagram illustrating a resonator for wireless powertransmission configured as a bulky type.

FIG. 11 is a diagram illustrating a resonator for wireless powertransmission configured as a hollow type.

FIG. 12 is a diagram illustrating a resonator for wireless powertransmission using a parallel-sheet.

FIG. 13 is a diagram illustrating a resonator for wireless powertransmission, the resonator including a distributed capacitor.

FIG. 14A is a diagram illustrating a matcher used by a 2D resonator.

FIG. 14B is a diagram illustrating a matcher used by a 3D resonator.

FIG. 15 is a diagram illustrating one equivalent circuit of theresonator for wireless power transmission illustrated in FIG. 8.

Throughout the drawings and the detailed description, unless otherwisedescribed, the same drawing reference numerals should be understood torefer to the same elements, features, and structures. The relative sizeand depiction of these elements may be exaggerated for clarity,illustration, and convenience.

DETAILED DESCRIPTION

The following detailed description is provided to assist the reader ingaining a comprehensive understanding of the methods, apparatuses and/orsystems described herein. Accordingly, various changes, modifications,and equivalents of the systems, apparatuses and/or methods describedherein may be suggested to those of ordinary skill in the art. Theprogression of processing steps and/or operations described is anexample; however, the sequence of and/or operations is not limited tothat set forth herein and may be changed as is known in the art, withthe exception of steps and/or operations necessarily occurring in acertain order. Also, descriptions of well-known functions andconstructions may be omitted for increased clarity and conciseness.

FIG. 1 illustrates a wireless power transmission system.

In one or more embodiments, a wireless power transmitted using thewireless power transmission system may be resonance power. However, itwill be appreciated that in other embodiments various othermethodologies for electromagnetic power transmission may be used;including wired and wireless technologies, for instance.

The wireless power transmission system may have a source-targetstructure including a source and a target. As shown in FIG. 1, thewireless power transmission system may include a resonance powertransmitter 110 corresponding to the source and a resonance powerreceiver 120 corresponding to the target being configured for thewireless transmission of electromagnetic energy.

The resonance power transmitter 110 may include a source unit 111 and asource resonator 115. The source unit 111 may be configured to receiveenergy from an external voltage supplier to generate resonance power.The resonance power transmitter 110 may further include a matchingcontrol 113 to perform resonance frequency or impedance matching forresonance power transmission via an inductive or magnetic coupling 101.

The source unit 111 may include, for example, one or more of: analternating current (AC)-to-AC (AC/AC) converter, an AC-to-directcurrent (DC) (AC/DC) converter, and/or a (DC/AC) inverter. The AC/ACconverter may adjust, to a desired level, a signal level of an AC signalinput from an external device. The AC/DC converter may output a DCvoltage at a predetermined level by rectifying an AC signal output fromthe AC/AC converter. The DC/AC inverter may be configured to generate anAC signal, for example, of a few megahertz (MHz) to tens of MHz band byquickly switching a DC voltage output from the AC/DC converter. ACvoltage output having other frequencies is also possible.

The matching control 113 may be configured to set a resonance bandwidthof the source resonator 115, an impedance matching frequency of thesource resonator 115 or both. The matching control 113 may include asource resonance bandwidth setting unit and/or a source matchingfrequency setting unit. The source resonance bandwidth setting unit mayset the resonance bandwidth of the source resonator 115, for example.The source matching frequency setting unit may be configured to set theimpedance matching frequency of the source resonator 115. In variousimplementations, a Q-factor of the source resonator 115 may bedetermined, for instance, based on setting of the resonance bandwidth ofthe source resonator 115 or setting of the impedance matching frequencyof the source resonator 115.

The source resonator 115 may be configured to transfer electromagneticenergy wirelessly to a target resonator 121. For example, in one or moreembodiments, the source resonator 115 may be configured to transfer theresonance power to the resonance power receiver 120 through inductivecoupling 101. The source resonator 115 may be configured to resonatewithin the set resonance bandwidth.

As shown in FIG. 1, the source resonator 115 may be configured toconvert electrical energy into magnetic energy for wireless transmissionof power through the inductive coupling 101 to the target resonator 121.The target resonator 121 in turn receives magnetic energy and convertsthe received magnetic energy into corresponding electrical energy. Thesource resonator 115 and the target resonator 121 forming the inductivecoupling 101 may be configured, for example, in a helix coil structuredresonator, a spiral coil structured resonator, a meta-structuredresonator, or the like. As such, the resonator power transmitter 110 andthe resonance power receiver may be physically spaced apart to permitpower transmission inductively without any wired connections therebetween.

The resonance power receiver 120 may include the target resonator 121, amatching control 123 configured to perform resonance frequency orimpedance matching, and a target unit 125 configured to transfer thereceived resonance power to a load.

The target resonator 121 may be configured to receive theelectromagnetic energy from the source resonator 115. The targetresonator 121 may also be configured to resonate within the setresonance bandwidth.

The matching control 123 may be configured to set at least one of aresonance bandwidth of the target resonator 121 and an impedancematching frequency of the target resonator 121. In variousimplementations, the matching control 123 may include a target resonancebandwidth setting unit and/or a target matching frequency setting unit.The target resonance bandwidth setting unit may set the resonancebandwidth of the target resonator 121 with the target matching frequencysetting unit configured to set the impedance matching frequency of thetarget resonator 121. In some implementations, a Q-factor of the targetresonator 121 may be determined based on setting of the resonancebandwidth of the target resonator 121 or setting of the impedancematching frequency of the target resonator 121.

The target unit 125 may be configured to transfer the received resonancepower to the device (load). The target unit 125 may include, forexample, an AC/DC converter and/or a DC/DC converter. In someimplementations, the AC/DC converter may generate a DC voltage byrectifying an AC signal transmitted from the source resonator 115 to thetarget resonator 121. And the DC/DC converter may supply a rated voltageto a device or the load by adjusting a voltage level of the DC voltage.

Referring to FIG. 1, a process of controlling the Q-factor may includesetting the resonance bandwidth of the source resonator 115 and theresonance bandwidth of the target resonator 121, and transferring theelectromagnetic energy from the source resonator 115 to the targetresonator 121 through inductive coupling 101 between the sourceresonator 115 and the target resonator 121. The resonance bandwidth ofthe source resonator 115 may be set, for instance, to be wider ornarrower than the resonance bandwidth of the target resonator 121.Accordingly, an unbalanced relationship between a BW-factor of thesource resonator 115 and a BW-factor of the target resonator 121 may bemaintained by setting the resonance bandwidth of the source resonator115 to be wider or narrower than the resonance bandwidth of the targetresonator 121.

In wireless power transmission employing a resonance scheme, theresonance bandwidth can be an important factor. For example, with theQ-factor (considering, for instance, one or more of: a change in adistance between the source resonator 115 and the target resonator 121,a change in the resonance impedance, impedance mismatching, a reflectedsignal, and/or the like), denoted as Qt, it has been found that Qt mayhave an inverse-proportional relationship with the resonance bandwidth,as given by Equation 1.

$\begin{matrix}\begin{matrix}{\frac{\Delta \; f}{f_{0}} = \frac{1}{Qt}} \\{= {\Gamma_{S,D} + \frac{1}{{BW}_{S}} + \frac{1}{{BW}_{D}}}}\end{matrix} & \left\lbrack {{Equation}\mspace{14mu} 1} \right\rbrack\end{matrix}$

In Equation 1, f₀ denotes a central frequency, Δf denotes a change in abandwidth, Γ_(S,D) denotes a reflection loss between the sourceresonator 115 and the target resonator 121, BWs denotes the resonancebandwidth of the source resonator 115, and BW_(D) denotes the resonancebandwidth of the target resonator 121. The BW-factor may indicate either1/BWs or 1/BW_(D), for example,

Due to one or more external factors including, for example, a change inthe distance between the source resonator 115 and the target resonator121, a change in a location of at least one of the source resonator 115and the target resonator 121, or the like, impedance mismatching betweenthe source resonator 115 and the target resonator 121 can occur. Theimpedance mismatching may be a direct cause in decreasing an efficiencyof power transfer. Thus, when a reflected wave corresponding to atransmission signal that is partially reflected and returned isdetected, the matching control 113 may be configured to determinewhether an impedance mismatching has occurred, and may also beconfigured to perform impedance matching. The matching control 113, forinstance, may change a resonance frequency by detecting a resonancepoint through a waveform analysis of the reflected wave. In oneimplementation, the matching control 113 may determine, as the resonancefrequency to be a frequency having a minimum amplitude in the waveformof the reflected wave.

An electromagnetic characteristic of many materials found in nature isthat they have a unique magnetic permeability or a unique permittivity.Most materials typically have a positive magnetic permeability or apositive permittivity. Thus, for these materials, a right hand rule maybe applied to an electric field, a magnetic field, and a pointing vectorand thus, the corresponding materials may be referred to as right handedmaterials (RHMs).

On the other hand, a material having a magnetic permeability or apermittivity which is not ordinarily found in nature or isartificially-designed (or man-made) may be referred to herein as a“metamaterial.” Metamaterials may be classified into an epsilon negative(ENG) material, a mu negative (MNG) material, a double negative (DNG)material, a negative refractive index (NRI) material, a left-handed (LH)material, and the like, based on a sign of the correspondingpermittivity or magnetic permeability.

One or more of the materials of the embodiments disclosed herein may bemetamaterials. The magnetic permeability may indicate a ratio between amagnetic flux density occurring with respect to a given magnetic fieldin a corresponding material and a magnetic flux density occurring withrespect to the given magnetic field in a vacuum state. The magneticpermeability and the permittivity, in some embodiments, may be used todetermine a propagation constant of a corresponding material in a givenfrequency or a given wavelength. An electromagnetic characteristic ofthe corresponding material may be determined based on the magneticpermeability and the permittivity. According to an aspect, themetamaterial may be easily disposed in a resonance state withoutsignificant material size changes. This may be practical for arelatively large wavelength area or a relatively low frequency area, forinstance.

FIG. 2A illustrates a diagram of a pad-type charging apparatus usingresonance power transmission including a source resonator 210 and atarget resonator 220.

A wireless charger 200 employs a “pad-type” charging scheme where amobile device is placed on a charging pad to wirelessly charge themobile device based on a resonance power transmission scheme, in thesame manner as the induction charging scheme. Wireless charging based onthe resonance power transmission scheme may use a near field magneticcoupling scheme and thus, when the distance between the source resonator210 and the target resonator 220 is close, for example, less than orequal to 1 cm, an impedance may rapidly vary.

When the distance between the source resonator 210 and the targetresonator 220 is less than or equal to several millimeters, an impedancemay widely and rapidly vary and thus, an efficiency of a resonator maydecrease in an operating frequency. The wide and rapid change in theimpedance may affect an input/output matching of a power amplifier thatsupplies a wireless power and an input/output matching of a rectifierthat converts a received AC power to a DC power. Accordingly, anefficiency of a wireless power transmission system may be deteriorated.

The wide and rapid change in the impedance may be minimized by impedancematching, for example, when a location 230 of the resonator 220 isslightly different from a matching location or when a plurality oftarget resonators are placed on the charging pad for a multi-targetdevice, the impedance of the resonator may vary again. Therefore, whenthe resonance power transmission scheme is used, a pad-type wirelesscharger may not be effective to obtain high wireless power transmissionefficiency.

Unlike a conventional induction scheme, a resonance power transmissionscheme may perform wireless power transmission even when a distancebetween a source resonator 210 and a target resonator 220 is more thanseveral dozen centimeters, for instance. Thus, even when a location of acenter of the source resonator 210 is different from a location of acenter of the target resonator 220, the wireless power transmission maybe effectively performed.

Wireless chargers using resonance power transmission for low-powermobile devices having a power-use level less than or equal to 10 watts(W) have been studied. FIG. 2B illustrates a plot of transmissionefficiency as a function of operation frequency when the distancebetween the source resonator 210 and the target resonator 220 is greaterthan or equal to a several dozen centimeters. FIG. 2C illustrates a plotof transmission efficiency as a function of operation frequency when thedistance between the source resonator 210 and the target resonator 220is less than or equal to several millimeters.

The plot illustrated in FIG. 2B, shows a transmission efficiency 240 maybe highest in an operating frequency where the target resonator 220 andthe source resonator 210 perform resonance power transmission. On theother hand, the plot illustrated in FIG. 2C, shows that a transmissionefficiency 250 may be lowest when the distance between the targetresonator 220 and the source resonator 210 is less than about severalmillimeters.

FIG. 3 illustrates a roof-type charging apparatus using resonance powertransmission.

As shown, the roof-type charging apparatus using resonance powertransmission may include a source resonance unit 310, a matching unit320, a connecting unit 330, an input power unit 340, a supporting unit350, a receiving unit 360, and a power converter 370.

According to an aspect, the charging apparatus may be configured as a“roof-type.” The term “roof-type,” as used herein, refers to a chargingapparatus including one or more resonator sources having a generallyplanar loop configuration defining a space therein. The resonatorsource(s) as such may be referred to as a “roof.” In some embodiments,the one or more source resonators may be configured as a circularstructure, an oval structure, an elliptical structure, a rectangularstructure, a square structure, triangular structure, polygonalstructure, or the like. An effective charging radius may be definedbased on the shape or geometry of the “roof” source resonator. One ormore target resonators which are to receive a charge wirelessly, suchas, for example, a battery, may be positioned inside the effectivecharging radius. The target resonators receive power transmissioninductively without any wired connections there between.

In the roof-type charging apparatus the source resonators may be spacedapart from the receiving unit. For instance, in some embodiments, thesource resonators and the receiving unit may be positioned generallyparallel with respect to one another. The distance between the sourceresonators and the receiving unit may be adjusted to provide impedancematching between the source resonator and a target resonator thatreceives the resonance power transmission. The connecting unit may beproviding between the source resonators and the receiving unit for suchpurposes.

As shown in FIG. 3, the source resonator 310 may be generallyrectangular or square-shaped. In one implementation, the sourceresonator 310 may have a size of 20 cm in length and 20 cm in width, forexample. The source resonator 310 may be connected to the matching unit320 and the connecting unit 330. A predetermined area of the frame ofthe source resonator may define a space therein and be connected to thematching unit 320 and/or the connecting unit 330.

The source resonance unit 310 may be configured to transmit a resonancepower through magnetic coupling regardless of a location of a resonatorincluded in a resonance power receiver, to the resonance power receiverlocated in a charging radius of the source resonator. The effectivecharging radius of the source resonator may be determined based on ashape of the source resonator. Advantageously, the source resonance unit310 may be configured to transmit the resonance power regardless ofwhether the source resonator and a target resonator included in theresonance power receiver directly face each other.

In various embodiments, the source resonance unit 310 may include agenerally planar source resonator that is square-shaped,rectangular-shaped, circle-shaped, triangle-shaped or polygon-shaped(octagon-shaped shown), for example. Of course, it will be appreciatedthat other shaped source resonators are also possible.

The source resonance unit 310 may also include an extension controllerthat controls a charging radius of a terminal by controlling a size ofthe source resonator. The extension controller may be configured tocharge or control the size of the source resonator and thus, mayincrease efficiency in transmitting a resonance power to the terminal inthe charging radius. In addition, the extension controller may controlthe size of the source resonator, and may control the charging radiusand thus, may charge multiple terminals. For example, the extensioncontroller may rotate the source resonance unit 310 using the connectingunit 330 as an axis. When the source resonance unit 310 rotates, thecharging radius where the terminal is charged may be extended.

The matching unit 320 may be located in a predetermined area of theframe of the source resonator, and may be configured to match, to apredetermined value, a coupling impedance between the source resonatorand at least one target resonator. For example, the matching unit 320may substantially match the coupling impedance between the sourceresonator and the at least one target resonator. The coupling impedancemay be match to within about 50 ohms, in some implementations. Thematching unit 320 may control the connecting unit 330 to control adistance between the source resonator and the at least one targetresonator for coupling impedance matching. And the matching unit 320 maybe connected to the source resonator, and may be located in and occupy apredetermined area inside or outside the roof of the source resonator.Also the matching unit 320 may be connected to the connecting unit 330.For example, the matching unit 320 may be located in an upper part ofthe connecting unit 330.

The connecting unit 330 may connect the source resonator to the inputpower unit 340 to enable the input power unit 340 to be separated by apredetermined length away from the source resonator. As such, theconnecting unit 330 may enable the source resonator and the matchingunit 320 to be separated by the predetermined distance or length awayfrom a ground. In some implementations, the predetermined length may beseveral dozen centimeters, for instance. The connecting unit 330 mayconnect the source resonance unit 310 to the input power unit 340.

The connecting unit 330 may be hollow cylinder, having a wirelessfrequency cable passes through the inside of the hollow cylinder. Forexample, the connecting unit 330 may be manufactured or otherwise formedas a plastic column of about 10 cm to 20 cm in length. And a radiofrequency (RF) cable may pass through the inside the hollow cylinder tothe source resonator from a power amplifier, for example. A distance orheight of the connecting unit 330 may be controlled for impedancematching between the source resonator and the at least one targetresonator. The connecting unit 330 may be manufactured from aninsulative material, for example, plastic, to avoid affecting theresonance frequency.

Input power unit 340 may be configured to generate the resonance powerbased on the resonance frequency, and may provide the resonance power tothe source resonator. For example, the input power unit 340 may includea frequency generator and a power amplifier. The frequency generator maygenerate an operating frequency so that the source resonator and the atleast one target resonator perform resonance power transmission. Invarious implementations, the operating frequency may be a resonancefrequency when an impedance of the source resonator and an impedance ofthe at least one target resonator are matched.

The power amplifier may be configured to amplify the resonance power inresponse to a request of the at least one target resonator in theoperating frequency. The amplified resonance power may be provided tothe source resonator. The input power unit 340 may be connected to theconnecting unit 330. For example, the input power unit 340 may includethe frequency generator and the power amplifier and thus, a weight ofthe input power unit 340 may comprise a significant portion of a weightof the roof-type charging apparatus using the resonance powertransmission.

The supporting unit 350 may be connected to the input power unit 340 andthus, may support the roof-type charging apparatus using the resonancepower transmission. The supporting unit 350 may support the roof-typecharging apparatus to prevent the roof-type charging apparatus using theresonance power transmission from falling over. For instance, thesupporting unit 350 may be connected to the input power unit 340 andthus, may prevent a center of gravity of the roof-type chargingapparatus using the resonance power transmission from being at the frontor rear of the roof-type charging apparatus. In one implementation, thesupporting unit 350 may be configured as a stand. The supporting unit350 may be manufactured to be thin to prevent affecting the resonancefrequency. The supporting unit 350 may be formed of an insulativematerial, for example, plastic, to avoid affecting the resonancefrequency.

The receiving unit 360 may be located in parallel with the sourceresonator and may receive the resonance power from the source resonatorthrough magnetic coupling. The resonance power receiver located in thereceiving unit 360 may receive the resonance power from the sourceresonator through the at least one target resonator. In one or moreembodiments, the resonance power receiver may be configured to charge abattery by converting the received resonance power to DC power using therectifier. It should be appreciated that the receiving unit 360 need notbe configured the same as the source resonance unit 310.

For example, the power converter 370 may convert AC power of a voltagesource to DC power. The power converter 370 may include a switching modepower supply (SMPS). The power converter 370 may convert AC powersupplied from an outside to DC power. The power converter 370 may thentransmit the DC power to the input power unit 340. The AC power may be220V in some instances.

In the roof-type charging apparatus using the resonance powertransmission, the matching unit 320 may be connected from thepredetermined area of the frame of the source resonator to a center areaof the source resonator, and the input power unit 340 may be locatedbelow the center area of the source resonator 310.

The roof-type charging apparatus using the resonance power transmissionmay include the matching unit 320 located in the center of the sourceresonator, the connecting unit 330 located under the matching unit 320,and the input power unit 340 located under the connecting unit 330. Forexample, the supporting unit 350 may be located in a bottom of the inputpower unit 340, and may support the roof-type charging apparatus usingthe resonance power transmission.

FIG. 4 illustrates a location where a target device is charged in aroof-type charging apparatus using resonance power transmission.

Referring to FIG. 4, first and second target devices 420 and 430 may beplaced at the bottom of a source resonator 410. The first and secondtarget devices 420 and 430 may receive a resonance power at a constantefficiency, for instance, even when the target devices 420 and 430 maybe located in an area 440 under the source resonator 410 that isdifferent an area defined by the source resonator 410.

For example, a charging radius 440 may be determined based on theresonance power transmission efficiency. In various implementations, acharging radius up to an area where the resonance power transmissionefficiency is about 70% may be determined as the charging radius. Theresonance power transmission efficiency may rapidly decrease when theresonance power transmission is attempted outside the charging radius.The charging radius of the source resonator 410 may be determined basedon a shape of the roof of the source resonator 410 and/or an intensityof the resonance power.

FIG. 5 illustrates resonance power transmission based on a location of atarget resonator in a resonance power receiver.

Referring to FIG. 5, the resonance power receiver may be placed in abottom of a source resonator 510. In this example, the resonance powerreceiver may include target resonators 530 and 550, a film, and abattery. When a resonance power is transmitted from the source resonator510 to the resonance receiver, an Eddy current may be induced by aconductor used for the resonance power receiver and the battery.Resonance power transmission efficiency unfortunately may decrease dueto the induced Eddy current. As such, functions of devices constitutinga resonance power transmitter and the resonance power receiver may bedamaged by the induced Eddy current.

The film may shield against a magnetic field generated due to the Eddycurrent, while the battery is charged with power. The film may have ahigh permeability and may have a low loss characteristic to minimizedifficulty generated due to the Eddy current. However, when a shieldingmaterial is located between a source resonator and a target resonator,an induction scheme may not be able to perform wireless powertransmission.

The resonance power receiver may also include a terminal in someembodiments. The terminal may be configured by covering a top of thebattery with a shielding material, such as the film, and place thetarget resonators 530 and 550 on the shielding material. Although, theinduction scheme may not be able to perform wireless power transmissionwhen shielding material exists between the target resonator 550 and thesource resonator 510.

Resonance power transmission may be effectively performed throughmagnetic coupling 520 when the target resonator 530 and the sourceresonator 510 face each other. However, it should be appreciated thateven when the target resonator 550 and the source resonator 510 do notface each other, the resonance power transmission scheme may stilleffectively perform resonance power transmission, through magneticcoupling 540. For instance, the resonance power may be transmitted in aradial pattern within a charging radius through magnetic coupling.

FIG. 6 illustrates various examples of source resonators. Although, itwill be appreciated that other source resonator configurations are alsopossible.

As shown, the roof of the source resonator may be configured, forexample, as a square or rectangle 610, a circle 620, a triangle 630, ora polygon 640 (octagon shown). An effective charging radius may bedetermined based on the shape of the roof of the source resonator.

FIG. 7 illustrates a roof-type charging apparatuses using resonancepower transmission.

Referring to FIG. 7, the roof-type charging apparatus using resonancepower transmission may be configured as a standard lamp. For example,the matching unit 320 may have a predetermined area and may be connectedfrom a frame of the source resonator to the center. For example, theshape of the roof of the source resonator may be configured as a squareor rectangle 710, a circle 720, a triangle 730, a polygon 740 (octagonshown), or the like

FIG. 8 illustrates a resonator 800 having a two-dimensional (2D)structure.

Referring to FIG. 8, the resonator 800 having the 2D structure mayinclude a transmission line, a capacitor 820, a matcher 830, andconductors 841 and 842. The transmission line may include, for instance,a first signal conducting portion 811, a second signal conductingportion 812, and a ground conducting portion 813.

The capacitor 820 may be inserted or otherwise positioned in seriesbetween the first signal conducting portion 811 and the second signalconducting portion 812 so that an electric field may be confined withinthe capacitor 820. In various implementations, the transmission line mayinclude at least one conductor in an upper portion of the transmissionline, and may also include at least one conductor in a lower portion ofthe transmission line. A current may flow through the at least oneconductor disposed in the upper portion of the transmission line and theat least one conductor disposed in the lower portion of the transmissionmay be electrically grounded. As shown in FIG. 8, the resonator 800 maybe configured to have a generally 2D structure. The transmission linemay include the first signal conducting portion 811 and the secondsignal conducting portion 812 in the upper portion of the transmissionline, and may include the ground conducting portion 813 in the lowerportion of the transmission line. As shown, the first signal conductingportion 811 and the second signal conducting portion 812 may be disposedto face the ground conducting portion 813 with current flowing throughthe first signal conducting portion 811 and the second signal conductingportion 812.

In some implementations, one end of the first signal conducting portion811 may be electrically connected (i.e., shorted) to a conductor 842,and another end of the first signal conducting portion 811 may beconnected to the capacitor 820. And one end of the second signalconducting portion 812 may be grounded to the conductor 841, and anotherend of the second signal conducting portion 812 may be connected to thecapacitor 820. Accordingly, the first signal conducting portion 811, thesecond signal conducting portion 812, the ground conducting portion 813,and the conductors 841 and 842 may be connected to each other, such thatthe resonator 800 may have an electrically “closed-loop structure.” Theterm “closed-loop structure” as used herein, may include a polygonalstructure, for example, a circular structure, a rectangular structure,or the like that is electrically closed.

The capacitor 820 may be inserted into an intermediate portion of thetransmission line. For example, the capacitor 820 may be inserted into aspace between the first signal conducting portion 811 and the secondsignal conducting portion 812. The capacitor 820 may be configured, insome instances, as a lumped element, a distributed element, or the like.In one implementation, a distributed capacitor may be configured as adistributed element and include zigzagged conductor lines and adielectric material having a relatively high permittivity between thezigzagged conductor lines.

When the capacitor 820 is inserted into the transmission line, theresonator 800 may have a property of a metamaterial, as discussed above.For example, the resonator 800 may have a negative magnetic permeabilitydue to the capacitance of the capacitor 820. If so, the resonator 800may be referred to as a mu negative (MNG) resonator. Various criteriamay be applied to determine the capacitance of the capacitor 820. Forexample, the various criteria for enabling the resonator 800 to have thecharacteristic of metamaterial may include one or more of thefollowing:, a criterion for enabling the resonator 800 to have anegative magnetic permeability in a target frequency, a criterion forenabling the resonator 800 to have a zeroth order resonancecharacteristic in the target frequency, or the like.

The resonator 800, also referred to as the MNG resonator 800, may alsohave a zeroth order resonance characteristic (i.e., having, as aresonance frequency, a frequency when a propagation constant is “0”). Ifthe resonator 800 has a zeroth order resonance characteristic, theresonance frequency may be independent with respect to a physical sizeof the MNG resonator 800. Moreover, by appropriately designing thecapacitor 820, the MNG resonator 800 may sufficiently change theresonance frequency without substantially changing the physical size ofthe MNG resonator 800 may not be changed.

In a near field, for instance, the electric field may be concentrated onthe capacitor 820 inserted into the transmission line. Accordingly, dueto the capacitor 820, the magnetic field may become dominant in the nearfield. In one or more embodiments, the MNG resonator 800 may have arelatively high Q-factor using the capacitor 820 of the lumped element.Thus, it may be possible to enhance power transmission efficiency. Forexample, the Q-factor indicates a level of an ohmic loss or a ratio of areactance with respect to a resistance in the wireless powertransmission. The efficiency of the wireless power transmission mayincrease according to an increase in the Q-factor.

The MNG resonator 800 may include a matcher 830 for impedance-matching.For example, the matcher 830 may be configured to appropriatelydetermine and adjust the strength of a magnetic field of the MNGresonator 800, for instance. Depending on the configuration, current mayflow in the MNG resonator 800 via a connector, or may flow out from theMNG resonator 800 via the connector. The connector may be connected tothe ground conducting portion 813 or the matcher 830. In some instances,power may be transferred through coupling without using a physicalconnection between the connector and the ground conducting portion 813or the matcher 830.

As shown in FIG. 8, the matcher 830 may be positioned within the loopformed by the loop structure of the resonator 800. The matcher 830 mayadjust the impedance of the resonator 800 by changing the physical shapeof the matcher 830. For example, the matcher 830 may include theconductor 831 for the impedance-matching positioned in a location thatis separate from the ground conducting portion 813 by a distance h.Accordingly, the impedance of the resonator 800 may be changed byadjusting the distance h.

In some instances, a controller may be provided to control the matcher830 which generates and transmits a control signal to the matcher 830directing the matcher to change its physical shape so that the impedanceof the resonator may be adjusted. For example, the distance h between aconductor 831 of the matcher 830 and the ground conducting portion 813may be increased or decreased based on the control signal. Thecontroller may generate the control signal based on various factors.

As shown in FIG. 8, the matcher 830 may be configured as a passiveelement such as, for example, the conductor 831. Of course, in otherembodiments, the matcher 830 may be configured as an active element suchas, for example, a diode, a transistor, or the like. If the activeelement is included in the matcher 830, the active element may be drivenbased on the control signal generated by the controller, and theimpedance of the resonator 800 may be adjusted based on the controlsignal. For example, when the active element is a diode is included inthe matcher 830, the impedance of the resonator 800 may be adjusteddepending on whether the diode is in an ON state or in an OFF state.

In some instances, a magnetic core may be further provided to passthrough the MNG resonator 800. The magnetic core may perform a functionof increasing a power transmission distance.

FIG. 9 illustrates a resonator 900 having a three-dimensional (3D)structure.

Referring to FIG. 9, the resonator 900 having the 3D structure mayinclude a transmission line and a capacitor 920. The transmission linemay include a first signal conducting portion 911, a second signalconducting portion 912, and a ground conducting portion 913. Thecapacitor 920 may be inserted, for instance, in series between the firstsignal conducting portion 911 and the second signal conducting portion912 of the transmission link, such that an electric field may beconfined within the capacitor 920.

As shown in FIG. 9, the resonator 900 may have a generally 3D structure.The transmission line may include the first signal conducting portion911 and the second signal conducting portion 912 in an upper portion ofthe resonator 900, and may include the ground conducting portion 913 ina lower portion of the resonator 900. The first signal conductingportion 911 and the second signal conducting portion 912 may be disposedto face the ground conducting portion 913. In this arrangement, currentmay flow in an x direction through the first signal conducting portion911 and the second signal conducting portion 912. Due to the current, amagnetic field H(W) may be formed in a −y direction. However, it will beappreciated that the magnetic field H(W) might also be formed in theopposite direction (e.g., the +y direction) in other implementations.

In one or more embodiments, one end of the first signal conductingportion 911 may be electrically connected (i.e., shorted) to a conductor942, and another end of the first signal conducting portion 911 may beconnected to the capacitor 920. One end of the second signal conductingportion 912 may be grounded to the conductor 941, and another end of thesecond signal conducting portion 912 may be connected to the capacitor920. Accordingly, the first signal conducting portion 911, the secondsignal conducting portion 912, the ground conducting portion 913, andthe conductors 941 and 942 may be connected to each other, whereby theresonator 900 may have an electrically “closed-loop structure.”

As shown in FIG. 9, the capacitor 920 may be inserted or otherwisepositioned between the first signal conducting portion 911 and thesecond signal conducting portion 912. For example, the capacitor 920 maybe inserted into a space between the first signal conducting portion 911and the second signal conducting portion 912. The capacitor 920 mayinclude, for example, a lumped element, a distributed element, or thelike. In one implementation, a distributed capacitor having the shape ofthe distributed element may include zigzagged conductor lines and adielectric material having a relatively high permittivity positionedbetween the zigzagged conductor lines.

When the capacitor 920 is inserted into the transmission line, theresonator 900 may have a property of a metamaterial, in some instances,as discussed above.

For example, when a capacitance of the capacitor inserted is a lumpedelement, the resonator 900 may have the characteristic of themetamaterial. When the resonator 900 has a negative magneticpermeability by appropriately adjusting the capacitance of the capacitor920, the resonator 900 may also be referred to as an MNG resonator.Various criteria may be applied to determine the capacitance of thecapacitor 920. For example, the various criteria may include, forinstance, one or more of the following: a criterion for enabling theresonator 900 to have the characteristic of the metamaterial, acriterion for enabling the resonator 900 to have a negative magneticpermeability in a target frequency, a criterion enabling the resonator900 to have a zeroth order resonance characteristic in the targetfrequency, or the like. Based on at least one criterion among theaforementioned criteria, the capacitance of the capacitor 920 may bedetermined.

The resonator 900, also referred to as the MNG resonator 900, may have azeroth order resonance characteristic (i.e., having, as a resonancefrequency, a frequency when a propagation constant is “0”). If theresonator 900 has the zeroth order resonance characteristic, theresonance frequency may be independent with respect to a physical sizeof the MNG resonator 900. Thus, by appropriately designing the capacitor920, the MNG resonator 900 may sufficiently change the resonancefrequency without substantially changing the physical size of the MNGresonator 900.

Referring to the MNG resonator 900 of FIG. 9, in a near field, theelectric field may be concentrated on the capacitor 920 inserted intothe transmission line. Accordingly, due to the capacitor 920, themagnetic field may become dominant in the near field. And, since the MNGresonator 900 having the zeroth-order resonance characteristic may havecharacteristics similar to a magnetic dipole, the magnetic field maybecome dominant in the near field. A relatively small amount of theelectric field formed due to the insertion of the capacitor 920 may beconcentrated on the capacitor 920 and thus, the magnetic field maybecome further dominant.

Also, the MNG resonator 900 may include a matcher 930 forimpedance-matching. The matcher 930 may be configured to appropriatelyadjust the strength of magnetic field of the MNG resonator 900. Theimpedance of the MNG resonator 900 may be determined by the matcher 930.In one or more implementations, a current may flow in the MNG resonator900 via a connector 940, or may flow out from the MNG resonator 900 viathe connector 940. And the connector 940 may be connected to the groundconducting portion 913 or the matcher 930.

As shown in FIG. 9, the matcher 930 may be positioned within the loopformed by the loop structure of the resonator 900. The matcher 930 maybe configured to adjust the impedance of the resonator 900 by changingthe physical shape of the matcher 930. For example, the matcher 930 mayinclude the conductor 931 for the impedance-matching in a locationseparate from the ground conducting portion 913 by a distance h. Theimpedance of the resonator 900 may be changed by adjusting the distanceh.

In some implementations, a controller may be provided to control thematcher 930. In this case, the matcher 930 may change the physical shapeof the matcher 930 based on a control signal generated by thecontroller. For example, the distance h between the conductor 931 of thematcher 930 and the ground conducting portion 913 may be increased ordecreased based on the control signal. Accordingly, the physical shapeof the matcher 930 may be changed such that the impedance of theresonator 900 may be adjusted. The distance h between the conductor 931of the matcher 930 and the ground conducting portion 913 may be adjustedusing a variety of schemes. For example, a plurality of conductors maybe included in the matcher 930 and the distance h may be adjusted byadaptively activating one of the conductors. Alternatively oradditionally, the distance h may be adjusted by adjusting the physicallocation of the conductor 931 up and down. For instance, the distance hmay be controlled based on the control signal of the controller. Thecontroller may generate the control signal using various factors. Asshown in FIG. 9, the matcher 930 may be configured as a passive elementsuch as, for instance, the conductor 931. Of course, in otherembodiments, the matcher 930 may be configured as an active element suchas, for example, a diode, a transistor, or the like. When the activeelement is included in the matcher 930, the active element may be drivenbased on the control signal generated by the controller, and theimpedance of the resonator 900 may be adjusted based on the controlsignal. For example, if the active element is a diode included in thematcher 930, the impedance of the resonator 900 may be adjusteddepending on whether the diode is in an ON state or in an OFF state.

In some implementations, a magnetic core may be further provided to passthrough the resonator 900 configured as the MNG resonator. The magneticcore may perform a function of increasing a power transmission distance.

FIG. 10 illustrates a resonator 1000 for a wireless power transmissionconfigured as a bulky type.

As used herein, the term “bulky type” may refer to a seamless connectionconnecting at least two parts in an integrated form.

Referring to FIG. 10, a first signal conducting portion 1011 and asecond signal conducting portion 1012 may be integrally formed insteadof being separately manufactured and thereby be connected to each other.Similarly, the second signal conducting portion 1012 and a conductor1041 may also be integrally manufactured.

When the second signal conducting portion 1012 and the conductor 1041are separately manufactured and then are connected to each other, a lossof conduction may occur due to a seam 1050. Thus, in someimplementations, the second signal conducting portion 1012 and theconductor 1041 may be connected to each other without using a separateseam (i.e., seamlessly connected to each other). Accordingly, it ispossible to decrease a conductor loss caused by the seam 1050. Forinstance, the second signal conducting portion 1012 and a groundconducting portion 1013 may be seamlessly and integrally manufactured.Similarly, the first signal conducting portion 1011, the conductor 1142and the ground conducting portion 1013 may be seamlessly and integrallymanufactured. A matcher 1030 may be provided that is similarlyconstructed as described herein in one or more embodiments.

FIG. 11 illustrates a resonator 1100 for a wireless power transmission,configured as a hollow type.

Referring to FIG. 11, each of a first signal conducting portion 1111, asecond signal conducting portion 1112, a ground conducting portion 1113,and conductors 1141 and 1142 of the resonator 1100 configured as thehollow type structure. As used herein, the term “hollow type” refers toa configuration that may include an empty space inside.

For a given resonance frequency, an active current may be modeled toflow in only a portion of the first signal conducting portion 1111instead of all of the first signal conducting portion 1111, the secondsignal conducting portion 1112 instead of all of the second signalconducting portion 1112, the ground conducting portion 1113 instead ofall of the ground conducting portion 1113, and the conductors 1141 and1142 instead of all of the conductors 1141 and 1142. When a depth ofeach of the first signal conducting portion 1111, the second signalconducting portion 1112, the ground conducting portion 1113, and theconductors 1141 and 1142 is significantly deeper than a correspondingskin depth in the given resonance frequency, it may be ineffective. Thesignificantly deeper depth may, however, increase a weight ormanufacturing costs of the resonator 1100 in some instances.

Accordingly, for the given resonance frequency, the depth of each of thefirst signal conducting portion 1111, the second signal conductingportion 1112, the ground conducting portion 1113, and the conductors1141 and 1142 may be appropriately determined based on the correspondingskin depth of each of the first signal conducting portion 1111, thesecond signal conducting portion 1112, the ground conducting portion1113, and the conductors 1141 and 1142. When each of the first signalconducting portion 1111, the second signal conducting portion 1112, theground conducting portion 1113, and the conductors 1141 and 1142 has anappropriate depth deeper than a corresponding skin depth, the resonator1100 may become light, and manufacturing costs of the resonator 1100 mayalso decrease.

For example, as shown in FIG. 11, the depth of the second signalconducting portion 1112 (as further illustrated in the enlarged viewregion 1160 indicated by a circle) may be determined as “d” mm and d maybe determined according to

$d = {\frac{1}{\sqrt{\pi \; f\; \mu \; \sigma}}.}$

Here, f denotes a frequency, μ denotes a magnetic permeability, and σdenotes a conductor constant. In one implementation, when the firstsignal conducting portion 1111, the second signal conducting portion1112, the ground conducting portion 1113, and the conductors 1141 and1142 are made of a copper and they may have a conductivity of 5.8×10⁷siemens per meter (S·m⁻¹), the skin depth may be about 0.6 mm withrespect to 10 kHz of the resonance frequency and the skin depth may beabout 0.006 mm with respect to 100 MHz of the resonance frequency.

A capacitor 1120 and a matcher 1130 may be provided that are similarlyconstructed as described herein in one or more embodiments.

FIG. 12 illustrates a resonator 1200 for a wireless power transmissionusing a parallel-sheet.

Referring to FIG. 12, the parallel-sheet may be applicable to each of afirst signal conducting portion 1211 and a second signal conductingportion 1212 included in the resonator 1200.

Each of the first signal conducting portion 1211 and the second signalconducting portion 1212 may not be a perfect conductor and thus, mayhave an inherent resistance. Due to this resistance, an ohmic loss mayoccur. The ohmic loss may decrease a Q-factor and also decrease acoupling effect.

By applying the parallel-sheet to each of the first signal conductingportion 1211 and the second signal conducting portion 1212, it may bepossible to decrease the ohmic loss, and to increase the Q-factor andthe coupling effect. Referring to the enlarges view portion 1270indicated by a circle, when the parallel-sheet is applied, each of thefirst signal conducting portion 1211 and the second signal conductingportion 1212 may include a plurality of conductor lines. The pluralityof conductor lines may be disposed in parallel, and may be electricallyconnected (i.e., shorted) at an end portion of each of the first signalconducting portion 1211 and the second signal conducting portion 1212.

When the parallel-sheet is applied to each of the first signalconducting portion 1211 and the second signal conducting portion 1212,the plurality of conductor lines may be disposed in parallel.Accordingly, a sum of resistances having the conductor lines maydecrease. Consequently, the resistance loss may decrease, and theQ-factor and the coupling effect may increase.

A capacitor 1220 and a matcher 1230 positioned on the ground conductingportion 1213 may be provided that are similarly constructed as describedherein in one or more embodiments.

FIG. 13 illustrates a resonator 1300 for a wireless power transmission,including a distributed capacitor.

Referring to FIG. 13, a capacitor 1320 included in the resonator 1300 isconfigured for the wireless power transmission. A capacitor used as alumped element may have a relatively high equivalent series resistance(ESR). A variety of schemes have been proposed to decrease the ESRcontained in the capacitor of the lumped element. According to anembodiment, by using the capacitor 1320 as a distributed element, it maybe possible to decrease the ESR. As will be appreciated, a loss causedby the ESR may decrease a Q-factor and a coupling effect.

As shown in FIG. 13, the capacitor 1320 may be configured as aconductive line having a zigzagged structure.

By employing the capacitor 1320 as the distributed element, it may bepossible to decrease the loss occurring due to the ESR in someinstances. In addition, by disposing a plurality of capacitors as lumpedelements, it is possible to decrease the loss occurring due to the ESR.Since a resistance of each of the capacitors as the lumped elementsdecreases through a parallel connection, active resistances ofparallel-connected capacitors as the lumped elements may also decreasewhereby the loss occurring due to the ESR may decrease. For example, byemploying ten capacitors of 1 pF each instead of using a singlecapacitor of 10 pF, it may be possible to decrease the loss occurringdue to the ESR in some instances.

FIG. 14A illustrates the matcher 830 used in the resonator 800 providedin the 2D structure of FIG. 8, and FIG. 14B illustrates an example ofthe matcher 930 used in the resonator 900 provided in the 3D structureof FIG. 9.

FIG. 14A illustrates a portion of the 2D resonator including the matcher830, and FIG. 14B illustrates a portion of the 3D resonator of FIG. 9including the matcher 930.

Referring to FIG. 14A, the matcher 830 may include the conductor 831, aconductor 832, and a conductor 833. The conductors 832 and 833 may beconnected to the ground conducting portion 813 and the conductor 831.The impedance of the 2D resonator may be determined based on a distanceh between the conductor 831 and the ground conducting portion 813. Thedistance h between the conductor 831 and the ground conducting portion813 may be controlled by the controller. The distance h between theconductor 831 and the ground conducting portion 813 can be adjustedusing a variety of schemes. For example, the variety of schemes mayinclude, for instance, one or more of the following: a scheme ofadjusting the distance h by adaptively activating one of the conductors831, 832, and 833, a scheme of adjusting the physical location of theconductor 831 up and down, or the like.

Referring to FIG. 14B, the matcher 930 may include the conductor 931, aconductor 932, a conductor 933 and conductors 941 and 942. Theconductors 932 and 933 may be connected to the ground conducting portion913 and the conductor 931. Also, the conductors 941 and 942 may beconnected to the ground conducting portion 913. The impedance of the 3Dresonator may be determined based on a distance h between the conductor931 and the ground conducting portion 913. The distance h between theconductor 931 and the ground conducting portion 913 may be controlled bythe controller, for example. Similar to the matcher 830 included in the2D structured resonator, in the matcher 930 included in the 3Dstructured resonator, the distance h between the conductor 931 and theground conducting portion 913 may be adjusted using a variety ofschemes. For example, the variety of schemes may include, for instance,one or more of the following: a scheme of adjusting the distance h byadaptively activating one of the conductors 931, 932, and 933, a schemeof adjusting the physical location of the conductor 931 up and down, orthe like.

In some implementations, the matcher may include an active element.Thus, a scheme of adjusting an impedance of a resonator using the activeelement may be similar as described above. For example, the impedance ofthe resonator may be adjusted by changing a path of a current flowingthrough the matcher using the active element.

FIG. 15 illustrates one example of an equivalent circuit of theresonator 800 for the wireless power transmission of FIG. 8.

The resonator 800 of FIG. 8 for the wireless power transmission may bemodeled to the equivalent circuit of FIG. 15. In the equivalent circuitdepicted in FIG. 15, L_(R) denotes an inductance of the powertransmission line, C_(L) denotes the capacitor 820 that is inserted in aform of a lumped element in the middle of the power transmission line,and C_(R) denotes a capacitance between the power transmissions and/orground of FIG. 8.

In some instances, the resonator 800 may have a zeroth resonancecharacteristic. For example, when a propagation constant is “0”, theresonator 800 may be assumed to have ω_(MZR) as a resonance frequency.The resonance frequency ω_(MZR) may be expressed by Equation 2.

$\begin{matrix}{\omega_{MZR} = \frac{1}{\sqrt{L_{R}C_{L}}}} & \left\lbrack {{Equation}\mspace{14mu} 2} \right\rbrack\end{matrix}$

In Equation 2, MZR denotes a Mu zero resonator.

Referring to Equation 2, the resonance frequency ω_(MZR) of theresonator 800 may be determined by L_(R)/C_(L). A physical size of theresonator 800 and the resonance frequency ω_(MZR) may be independentwith respect to each other. Since the physical sizes are independentwith respect to each other, the physical size of the resonator 800 maybe sufficiently reduced.

Example embodiments may provide a roof-type charging apparatus usingresonance power transmission, and the roof-type charging apparatus mayenable a source resonator and a target device to be separated by apredetermined distance away from each other and thus, may stabilize acoupling impedance of two resonators to be a predetermined impedance.

Example embodiments may provide a roof-type charging apparatus usingresonance power transmission, and the roof-type charging apparatus maystabilize a coupling impedance to be a predetermined impedance and thus,a power amplifier and a rectifier may be easily matched.

Example embodiments may provide a roof-type charging apparatus usingresonance power transmission, and the roof-type charging apparatus maystabilize a coupling impedance to be a predetermined impedance and thus,a change in the impedance may be low and multiple target devices may becharged.

Example embodiments may adjust a size of a source resonator and thus, acharging radius where a target device is charged may be controlled andmultiple target devices may be charged.

In various embodiments, one or more of the processes, functions, methodsdescribed above may be recorded, stored, or fixed in one or morecomputer-readable storage media that includes program instructions to beimplemented by a computer to cause a processor to execute or perform theprogram instructions. The media may also include, alone or incombination with the program instructions, data files, data structures,and the like. The media and program instructions may be those speciallydesigned and constructed, or they may be of the kind well-known andavailable to those having skill in the computer software arts. Examplesof computer-readable media include magnetic media, such as hard disks,floppy disks, and magnetic tape; optical media such as CD ROM disks andDVDs; magneto-optical media, such as optical disks; and hardware devicesthat are specially configured to store and perform program instructions,such as read-only memory (ROM), random access memory (RAM), flashmemory, and the like. Examples of program instructions include machinecode, such as produced by a compiler, and files containing higher levelcode that may be executed by the computer using an interpreter. Thedescribed hardware devices may be configured to act as one or moresoftware modules in order to perform the operations and methodsdescribed above, or vice versa. In addition, a computer-readable storagemedium may be distributed among computer systems connected through anetwork and computer-readable codes or program instructions may bestored and executed in a decentralized manner.

It is understood that the terminology used herein, may be different inother applications or when described by another person of ordinary skillin the art.

A number of example embodiments have been described above. Nevertheless,it should be understood that various modifications may be made. Forexample, suitable results may be achieved if the described techniquesare performed in a different order and/or if components in a describedsystem, architecture, device, or circuit are combined in a differentmanner and/or replaced or supplemented by other components or theirequivalents. Accordingly, other implementations are within the scope ofthe following claims.

What is claimed is:
 1. A roof-type charging apparatus using resonancepower transmission comprising: a source resonance unit configured totransmit resonance power including a source resonator having a generallyplanar loop configuration and defining a space therein; a receiving unitconfigured to receive the resonance power transmitted from the sourceresonator; and a connecting unit configured to separate the sourceresonator and the receiving unit by a predetermined distance.
 2. Theapparatus of claim 1, wherein the source resonator and the receivingunit are positioned generally parallel with respect to one another. 3.The apparatus of claim 1, wherein the source resonator is one of:square-shaped, rectangular-shaped, circle-shaped, oval-shaped,elliptical-shaped, triangle-shaped, octagon-shaped and polygon-shaped.4. The apparatus of claim 1, wherein the source resonator defines aneffective charging radius of the source resonator.
 5. The apparatus ofclaim 4, wherein a target resonator that receives the resonance powertransmission is positioned inside the effective charging radius of thesource resonator.
 6. The apparatus of claim 1, further comprising: aninput power unit configured to generate a resonance power based on aresonance frequency, and to provide the resonance power to the sourceresonator.
 7. The apparatus of claim 6, wherein the input power unit islocated below the space defined by the source resonator.
 8. Theapparatus of claim 1, further comprising: a matching unit configured tomatch a coupling impedance of the source resonator and a targetresonator that receives the resonance power transmission.
 9. Theapparatus of claim 8, wherein the matching unit is positioned in thespace defined by the source resonator.
 10. The apparatus of claim 1,wherein the source resonance unit includes a frame configured to connectthe source resonator to the connecting unit.
 11. The apparatus of claim1, further comprising: a power converter configured to convertalternating current (AC) power of a voltage source to a direct current(DC) power.
 12. The apparatus of claim 1, wherein the connecting unitcomprises a hollow cylinder, and a cable passing through the inside ofthe hollow cylinder.
 13. The apparatus of claim 11, wherein the hollowcylinder is formed of an insulative material.
 14. The apparatus of claim1, wherein the predetermined distance is adjustable thereby providingimpedance matching between the source resonator and a target resonatorthat receives the resonance power transmission.
 15. The apparatus ofclaim 1, wherein the source resonance unit includes an extensioncontroller configured to adjust an effective charging radius of thesource resonator.
 16. The apparatus of claim 1, further comprising: asupporting unit configured to support the apparatus.
 17. A method oftransmitting resonance power comprising: transmitting resonance powerusing a source resonator having a generally planar loop configurationdefining a space therein; and receiving with a receiving unit theresonance power transmitted from the source resonator, wherein thesource resonator and the receiving unit are separated by a predetermineddistance.
 18. The method of claim 17, wherein the source resonator isone of: square-shaped, rectangular-shaped, circle-shaped,triangle-shaped, octagon-shaped and polygon-shaped.
 19. The method ofclaim 17, wherein the source resonator defines an effective chargingradius of the source resonator.
 20. The method of claim 17, wherein atarget resonator that receives the resonance power transmission ispositioned inside the effective charging radius of the source resonator.21. The method of claim 17, further comprising: adjusting thepredetermined distance to provide impedance matching between the sourceresonator and a target resonator that receives the resonance powertransmission.
 22. The method of claim 17, further comprising: adjustingan effective charging radius of the source resonator.
 23. A roof-typecharging apparatus using resonance power transmission comprising: asource resonance unit configured to transmit resonance power including asource resonator having a generally planar loop configuration anddefining a space therein; a receiving unit configured to receive theresonance power transmitted from the source resonator; a matching unitlocated in a predetermined area of a frame of the source resonator andconfigured to match, to a predetermined value, a coupling impedancebetween the source resonator and at least one target resonator thatreceives the resonance power transmission; an input power unitconfigured to generate resonance power based on a resonance frequency,and to provide the resonance power to the source resonator; a connectingunit configured to separate the source resonator and the receiving unitby a predetermined distance; and a supporting unit connected to theinput power unit and configured to support the roof-type chargingapparatus.